Testosterone is most commonly used in the United States as the cypionate
and the enanthate esters.
Doctors often administer both forms of testosterone
as infrequently as every two weeks and in some cases every month because of
misinformation about the frequency of administration in the Physician's Desk
Reference.

I have consistently heard people
who are given these forms of testosterone complain of a large
decrease in energy, libido, clarity of thought, and mood, by the time the two
or four week administration occurs.
An analysis of the published literature that details the pharmacokinetics
of these drugs show that this is inappropriate if the most consistent blood-levels
of the drugs are desired.

One study stated that 140 mg. of testosterone cypionate and testosterone enanthate
produced similar blood levels after injection, and stated that heightened blood
levels decreased to basal levels by day ten.1 With higher doses the
duration appears to increase a little as another study stated that with an
injection of 200 mg. of testosterone cypionate blood levels reached basal levels
by days 13 to 14.2

Looking at the chart, it is easy to see why a person would feel
a large decline in energy, libido, stamina, mood, and overall quality of life
with two or three week dosing, so I urge the physician to consider adjusting
dosing strategies. I consistently see people experience the greatest quality
of life improvement when testosterone cypionate or enanthate are administered once every seven days.

Source: Schulte-Beerbuhl, 1980

There are forms of testosterone that are not available in the
United States that are designed to provide longer duration of release. These products,
which include Sustanon and Durateston, are typically blends of longer and shorter
acting testosterone esters that release more gradually. They provide a more
consistent release with less peak/trough effect than cypionate/enanthate.

Frequency of Administration - Nandrolone Decanoate (Deca Durabolin)

Pharmacokinetic studies with nandrolone decanoate also show that it is more desirable
to administer it on a weekly basis rather than bi-weekly or monthly if the most
consistent blood levels of the steroid are desired.

While blood levels of nandrolone
rise in several hours, the mean half-life of the nandrolone decanoate is approximately
20 percent longer than testosterone cypionate.

Note that dosing information
in the package insert for nandrolone decanoate recommends weekly administration.
The package inserts for testosterone
cypionate and testosterone enanthate should be updated, as these forms of
testosterone have an even shorter lifespan in the body than nandrolone.

Note
that with oil-based steroids like the testosterones and nandrolone there can
be a pool of the drug that accumulates in the injection site area that lengthens
the decline in blood levels somewhat after several injections. Still, after
watching many people over the last several years, I have seen that for most
consistent blood level of the drug and best overall patient quality of life,
weekly administrations work best.

If
your doctor won't consider prescribing weekly testosterone injections, print
this article and the contents of this link out and share it with your doctor.

Disclaimer:
This article is provided for educational purposes only, and is in no way a substitute
for the advice of a qualified medical doctor or a recommendation to do other
than your doctor determines is best for you. You should present this information
to your doctor for their analysis because appropriate medical therapy and the
use of pharmaceutical compounds like anabolic steroids should be tailored by
a knowledgeable doctor for the individual as no two individuals are alike. I
do not recommend self-medicating with any pharmaceutical drug as you should
consult with a qualified medical doctor who can determine your individual situation.
If you use the information I present without the approval of your doctor, you
do so strictly at your own risk and no responsibility is implied or intended
on my part.